Before long, 150 volunteers had showed up to help Merritt's family and the Missouri State Highway Patrol search for Merritt and her dog. Clark Parrott, a sergeant with the MSHP, told ABC that the patrol sent a helicopter to use infrared radar to scan the farm area near Merritt's home.

The search revealed nothing, though, so the group of locals and law enforcement took a break and started their efforts up again at dawn. At this point, Parrott said they began using a grid search to comb through the farm's cornfields, which consist of five-foot-high stalks. The team used dogs to help search too.

Three hours later, one of the rescue dog's barks received a much weaker bark in response. Turns out the weaker bark came from Fat Heath, who had stayed with his owner in the cornfields all night, Parrott told ABC.

It was this bark that led the team to Merritt, who was unharmed, save for some dehydration and mosquito bites, according to Parrott.

Parrott was both relieved and concerned when the team found the girl. He told ABC that watching the dogs yapping at each other was a "neat little moment."

Merritt and her Yorkie were taken back home safely afterward. A dog's loyalty truly knows no bounds.

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